Diseases of the central nervous system (CNS), including the brain, the brainstem, the spinal cord and peripheral nerves, often result in serious morbidity, death or impairment of mobility. Due to the presence of the blood brain barrier, many therapeutic agents can not enter the brain from the blood. Thus, in order to treat a neurological disorder, therapeutic agents must be directly injected into the brain.
It is desirable that a therapeutic agent to treat a CNS disease be delivered to the brain in a therapeutically effective amount. If too little therapeutic agent is administered, the disease will not be effectively treated. On the other hand, if too much therapeutic agent is administered, the therapeutic is wasted, a consequence which is particularly undesirable when the therapeutic agent is expensive or otherwise difficult to obtain. Therefore, it is important to monitor and determine the amount of therapeutic that is delivered to the brain. Methods for monitoring therapeutic agents acutely delivered to the CNS by convection enhanced delivery (CED) have been previously described in U.S. Pat. No. 7,371,225.
In addition, the distribution of any agent injected into the brain cannot be predicted due to the presence of multiple brain regions and anatomical difference from patient to patient or caused by the CNS disease. Therefore, the ability to effectively treat a CNS disorder with a therapeutic agent may be compromised by an inability to effectively determine the rate of delivery, as well as the inability to determine the effective amount of a therapeutic composition within and across multiple brain regions.
For the foregoing reasons, there is a need for a composition to treat a CNS disease, as well as systems and methods to determine and administer an effective amount of a therapeutic composition for treating a CNS disorder.